BoM Assistance - Reversible DC Motor + Speed control

Hi Folks,

Looking for some assistance on developing a bill of materials I will need for a small project.

Just purchased myself an Elegoo Saturn and want to build a wash station like the Anycubic Wash&Cure using an Arduino Nano and DC motor.

My requirements I put together are

  • 12v input (Plan is to use standard 12v barrel jack connector
  • Arduino Nano R3 controlled
  • Reversible DC Motor (plus driver, L298N Perhaps?)
  • 3 Position rotary Switch (Time, Linked to variable in s in the sketch)
  • Potentiometer (Speed, using PWM or similar to the motor, read from analog in the sketch)
  • Master on off switch
  • GO! Switch (Momentary)

The Idea is to select a time from the rotary switch which selects a value in the sketch to turn the motor in one direction for half the selected time, then reverse the motor gentry and spin the other way for the time remaining. I can piece together the code from the lovely example sketches people provide but need some help with all the mechanical parts i would need

I have seen people build simple stirring plates using a PC fan, but I would like to reverse the direction and add a timer using an arduino, because why make an apple pie when you can create the universe right?

If im miles out with what I'm thinking please let me know, im not new to tinkering with electronics but my ears are still a little damp. Directions to helpful videos or projects that would help along the way are greatly appreciated

12v input (Plan is to use standard 12v barrel jack connector

Think twice about powering the Arduino through the Vin or the power jack. Powering through Vin or the power jack means that the Arduino and all peripherals that are on the 5V rail are powered by the onboard 5V regulator. The on board 5V regulator is not heat sinked so will supply limited current before it overheats and shuts down. The recommend max power dissipation for the regulator is 1 Watt. With 12V into the regulator the max current is about 140 mA (1W / (12V - 5V)). The Arduino uses around 50ma of that leaving less than 90mA (max) for everything else. I would use a buck converter to drop the 12V to 5V and connect that to the 5V on the Arduino, bypassing the, weak, 5V regulator.

Reversible DC Motor (plus driver, L298N Perhaps?)

The L298 is an ancient and very inefficient BJT output motor driver. Pololu (and others) offer modern MOSFET output drivers. The Pololu pages have good tutorials on the use of their divers.